In recent years, with rapid development of wireless communications technologies, a quantity of wireless users increases sharply; and a service requirement also increases sharply. As various new wireless services emerge, people have a higher requirement on a communication rate. However, spectrum resources applicable to wireless communication are limited. Therefore, to provide a high enough data communication rate by using the limited spectrum resources to meet a user requirement, it is extremely important to improve spectrum utilization.
Currently, in a frequency division duplex (FDD) system, a mobile broadband (MBB) service is obviously asymmetrical, and a downlink service volume is three times an uplink service volume. Consequently, downlink spectrum resources are not sufficient, while uplink spectrum resources are usually in an idle state.
Therefore, how to maximize utilization of spectrum resources for service transmission is a problem to be resolved in the present invention.